Total Solar Eclipse of 2020 December 14
Flight from São Paulo, Brazil, or Cape Town, South Africa
Thanks to the numerous border closures and restrictions caused by the Covid-19 pandemic it became clear going to either Chile or Argentina would be difficult at best. So in September 2020 I started working on a special eclipse flight using a private jet out of either São Paulo in Brazil or else Cape Town in South Africa which at the time for the latter still had its borders open to most foreigners. The master plan for the flight was to execute a 6 to 7.5-hour loop to intercept the eclipse path above the Southern Atlantic Ocean. From São Paulo we could also execute an intercept above the Pacific Ocean with a 10-hour flight which the aircraft can handle. That said factoring in the costs is always the limiting factor. As the solar elevation above Chile and Argentina is too high to be able to use an aircraft unless it has zenithal windows I did study two options at both ends of the eclipse path for this flight, the first from French Polynesia and the second from South Africa, plus a third one from Brazil. The key to success is also to be able to find countries which have their borders open to foreigners and reasonable restrictions such as a negative PCR test 72 hours before departure and a mandatory installation of a tracing application on your smartphone. Technically speaking a flight out of French Polynesia would have been more demanding and more expensive, so a departure from either São Paulo or Cape Town was chosen as being optimal. Moreover such a choice allows to observe from São Paulo a 31% partial solar eclipse and from Cape Town a sunset partial solar eclipse at maximum with a 60% obscuration should something really go wrong with the eclipse flight. It’s worth to mention that South Africa is the only country outside of Chile and Argentina which can offer this combination; of course seeing a deep partial from other countries in South America is possible, yet an eclipse flight from those countries isn’t realistic, but possibly from Brazil. Mise à jour Covid-19: following the reopening of the borders in Chile starting on November 23rd and the new protocols for foreigners in Argentina the eclipse flight is now put on standby. In the event the sky is cloudy another contingency flight of 8 to 9 hours will be activated.
The graphic below tells you more about some of the parameters that were involved in the decision making of this eclipse flight. The eclipse path in the background is there to put the other parameters into context, yet is not in perfect sync with those parameters. First we need to choose a solar elevation allowing the passengers to observe the eclipse comfortably through the windows of the aircraft. An elevation of less than 40 degrees is usually recommended for most aircrafts in order to avoid too many contortions and also optical distortions on the cabin windows; on the flight out of South Africa we’ll get by with 20 degrees which is convenient, and under 40 degrees on the one out of Brazil but with a much longer totality duration. You will also notice that the totality duration decreases sharply at both ends of the eclipse path and with a solar elevation of 20 degrees the duration is more than halved which is a major down side. It is worth to mention that a flight out of French Polynesia was also considered, however the operationnal costs were too high.
In the end only the flight out of São Paulo in Brazil was retained because it was the one providing the best balance from the technical, financial, international accessibility and sanitary restrictions standpoints.